Clamp for panel instruments



A. URFER 1,835,728

CLAMP FOR PANEL INSTRUMENTS Filed NOV. 9, 1929 g\\ JNVEQVTOR. 22 V 24 ADOLF URFER F may 5 C0 5 /GM/'r M GL ATTORNEYS.

' Patented Dec. 8, 1931 UNITED STATES ADOLF URFER,

YO K

F BROOKLYN, NEw YORK, COMPANY, INCORPORATED, 0F BROOKLYN,

AssmNOR r0 PIONEER INSTRUMENT NEW YORK, A CORPORATION or NEW CLAMP FOR PANEL INSTRUMENTS Application filed November This invention relates to clamps for panel instruments.

Many instruments are, by common practice, mounted upon a panel or instrument board 5 at the rear of the panel and project through, an aperture in the panel. Instruments have been supporte in suchapertures by clamps en aging a ring or other projection, extending rom each instrument and abutting the. rear side "of the panel. Various forms of clamps have been suggested by which the projection or ring is held firmly. in place against the panel, but of those changes with which I am familiar,

' where an instrument is to be removed from a panel upon which many instruments are mounted and especially when the panel is in place in the cock-pit of an airplane or even in an automobile.

This is so particularly in aircraft installations where space must be efliciently utilized and instruments are more or less crowde with the result that it is a task requiring perseverance and patience to remove and replace an instrument. The inaccessibility o the rear of the panel and the difiiculty to be encountered in manipulating the usua clamps is the cause of waste of much of the time now required to effect replacement of an instrument and in View I have developed a clamp which takes care of itself during a loosening operation and when loosened. member or bridge which bears upon the projection or rin of an instrument is maintained in frictional contact with a rota-table member so that as the rotatable member is rotated to relieve the clampin force the bridge is \rotated out of range 0 the projection or ring. er the instrument is free the clamp is maintained in its last position from which it may be easily moved to its useful clamping position by rotation in a reverse direction.

Among the objects of my invention is to provide clamping means for panel,, instruments which requires but very little handling during removal and replacement-pf an in- 5 strument.

1 the clamp 1s Briefly, the clamping P 9, 1929. Serial No. 405,905.

Another Object is to provide a clamping member capableof maintaining the relation it is left in in respect-to the panel upon which it is mounted.

Other objects and advantages will be pointed out hereinafter in the description which follows and in the claim.

In the drawings:

Fig. I is a sectional detail of a clamp in clamping relation with an instrument.

Fi II is a view from the rear of a panel showin the clamp of Fig. I.

Fig. II is an exploded view of the clamp shown in Figs. I and II. Fig. IV is a view from the rear of a panel showing a clamp embodying my invention modified so as to clamp two adjacent instruments? Fig. V is a front view of a panel showing the use of five clamps to support four instruments.

The form of clamps illustrated in Figs. I,

d II and III has a bridge member 10 which has one end 11 turned over at an angle 0 90 to form a leg by which that end of the f bridge may be supported against the rear surface of panel 12. The other end 13, when functioning to hold an inst-rument in place, rests upon a ring 1 1 or other projection extending from an instrument 15, Figs. I and II. Ring 14 which may be considered as a part of the instrument, abuts the rear surface of panel 12 and serves to fix the osition of the instrument relatively to the panel while at the same time permitting the front of the instrument to extend into and through an aperture so that it may be viewed as readily seen in Fig. An edge of a panelaperture is illustrated at 16 in Figs. I and II In addition to bridge 10 the clamp includes the bolt a bolt17, a nut 18 and a spring 19, having a non-rotatable head 20 which engages a similarl shaped hole in the panel,

'g. I. As may be clearly seen in Fig. I bolt 17 extends rearwardly and spring 19, which is mounted upon the shank of the bolt, is compressed between the panel and bridge when the bridge is functioning to hold an instrument in' place. The bridge acts as a would be ends with the result tension placed upon duty the same as though no spring were upon a looseningup of the clamp the spring is effective to raise the bridge in frictional contact with the nut. Accordingly, as the nut is rotated, during a loosening operation of the clamp, the bridge will be rotated with the nut by virtue of the frictional relation between the two'members.

aving reference to Fig. II, which is a the clamp shown in provided for permitting c ear the wall 27 of the instrument as it is rotated counter clockwise (for a right handed screw). The width of th to clear the edge of ring 14 when it has been rotated 90.

amount of handlin formerly required the operation just descriIied, it is characteristic of the clamp th not of itself change the position in which it was last left; that is to say, the bolt may not wobble and possibl extend forwardl of the panel, the bri ge may not by itself assume another posiby rotaton about the bolt nor be disp aced axially of the bolt so as to interfere with the repositionin of an instrument. In fact, it remains just w ere it is last and a mechanic may except to find it in such a position and know even though he cannot see it.

, Upon replacing an instrument, without first having had to readjust and hold at least two clamps out of interfering positions, the

clamps and until the bridge is brought tact with the ring of the instrument.

The initial rotation (of approximately 90) carries the bridge with the nut to its clamping position, Figs. I and II, and thereafter, subsequent rotation cause the clamp to seize hold the instrument in mounted position.

. In Fig. IV I have illustrated another form of clamp Whichis operable in the manner described and possesses characteristics common to the clamp shown in Figs. I and II. This clamp has a bolt 17, nut 18 and spring 19, but the bridge 28 is a bar or stri p of uniform crossseetion across its narrow dimension and it is designed to act upon two instruments at once. The ends of the bar 28 are supported by rings i of respective instruments 31, 32 and it is preferable to also provide. projections 33, 34 for better support. "hile bar 28 might have forms and proportions, other than those illustrated in Fig. IV, I prefer to round one end of the bar at 35 so as to clear wall 36 of instrument 32 during a clamp relieving make a diagonal cut 37 at the other end so as to permit the use of the clamp providing an abundance of footing for supporting'that end of the bar.

The two forms of clamp are particularly useful since their use enables the total number of clamps necessary for a particular installation to be maintained a minimum. For example, instead of using eight or more individual clamps similar to the form illustrated I to hold four instruments in there a saving in the appreciated thatthe highcapable of fulfillingthe objects primarily stated, I wish it to be understood that I contemplate changes her modifications embodying. the principle of my invention and coming within the scope of the appended claim. If neatness were not an almost indispensable requirement for the appearance of the front of a panel I would so fashion the screw-engaged relatively rotatable members as to make the rotatable member, or nut, accessible from the front so that the necessity of handling the similar member from the rear of the panel as m the forms illustrated, would be eliminated.

I claim:

In a clamp for panel instruments, the combination of a bridge engageable with an instrument on each side of the clamp for bolding two instruments in position on a panel, means engaging said bridge and engageable' when the first member is rotated, and resilient means for urging said bridge into frictional engagement with the rotatable member when the clamp is in use on a panel so that said bridge rotates with said member to clear the instruments when the member is initially rotated to loosen the clamp.

In testimony whereof I hereto afiix my signature. no ADOLF URFER. 

